Perhaps no gemstone has been as prized throughout history
as the ruby. Celebrated in the Bible and in ancient
Sanskrit writings as the most precious of all gemstones,
rubies have adorned emperors and kings and inspired
countless legends and myths with their rich, fiery hues.

As the ultimate red gemstone, rubies have symbolized
passion and romance for centuries. Ruby is the birthstone
for July and is also the recommended gem for couples
celebrating their 15th and 40th wedding anniversaries.

Also the color of blood, the stone is symbolic of courage
and bravery. Warriors were said to have implanted rubies
under their skin to bring them valor in battle and make
them invincible. The stone has also been used as a talisman
against danger, disaster, to stop bleeding, and a number
of other ailments. Its intense color was thought to
come from an undying flame inside the stone - or, as
some legends would have it, a piece of the planet Mars.

Ruby is the red variety of corundum, a sister of sapphire.
Like sapphire, ruby rates a "9" on the Mohs
scale of hardness, making it the second hardest material
known after diamonds.

The most valuable rubies come from Myanmar (formerly
Burma), but they are mined throughout Southeast Asia.
Good quality stones come from Thailand, Sri Lanka, and
Vietnam. Kenya and Tanzania also are becoming more important
as mining sources for ruby. But while the color of the
stones from East Africa rivals the world's best rubies,
most of these stones are fraught with inclusions that
diminish their transparency and value. However, the
East African stones are displayed to full advantage
in cabochon cuts and have done well in the mass jewelry
market. Meanwhile, Afghanistan, Pakistan and Russia
have all produced occasional top-quality rubies, but
the rough terrain in these areas has made mining difficult.

The most important factor to consider when buying a
ruby is its color. It comes in a variety of shades ranging
from purplish- and bluish-red to orange-red. Like sapphire,
there is also a translucent variety of ruby that can
display a six-point star when cut in a smooth domed
cabochon cut.

The finest rubies are intensely saturated, pure red
with no overtones of brown or blue. After color, the
factors that influence value are clarity, cut and size.
Rubies that are clear with no visible inclusions are
more valuable than those with visible internal flaws.

Rubies are readily available in sizes up to 2 carats,
and because of their intense color and durability, they
make excellent accent stones. Larger sizes can be obtained,
but top-quality rubies are rarer and more valuable than
colorless diamonds - particularly in sizes above 5 carats.
For instance, a 16-carat ruby sold at auction for $227,301
at Sotheby's in 1988. A 27.37-carat Burmese ruby ring
sold for $4 million at Sotheby's in Geneva, Switzerland,
in May 1995 - an astounding $146,145 per carat. In contrast,
none of the D-color, internally flawless diamonds over
50 carats sold in the last decade can match this value
per carat.

Rubies are rarely found perfect in nature - which is
why many are heat-treated to intensify or lighten their
color or improve their clarity. Heat enhancement is
a permanent, stable process. Some rubies also have surface
fractures and cavities that are filled with glass-like
materials to improve their appearance. This filler may
break, fall out or wear out over time if exposed to
heat, strong abrasives or constant impact. For both
treated or untreated stones, the safest cleaning method
is to just use soapy water or a mild commercial solvent
and a brush.